Water-seal trap.



PATENTED AUG. 2, 1904.

J. E. KEYT.

WATER SEAL TRAP.

APPLICATION FILED MAY 28. 1903.

N0 MODEL.

Wane-S888.

UNITED STATES Patented August 2, 1904.

JOHN E. KEYT, OF SAN FRANCISCO, CALIFORNIA.

WATER-SEAL TRAP.

SPECIFICATION forming part of Letters Patent No. 766,764, dated August2, 1904.

Application filed May 28, 1903. Serial No. 159,058 (No model.)

To all whom, it may concern:

Be it known that I, JOHN E. KEYT, a citizen of the United States, and aresident of the city and county of San Francisco and State ofCalifornia, have invented a new and useful Improvement in \Vater-SealTraps, of which the following is a specification.

This invention relates to improvements made in traps for waste-pipes andsewer-pipes that have a curved body or depressed portion adapted toretain a body of water for a water seal. In traps of this descriptionthe body of water held in the bend prevents the passage of foul gas andodors past that point; but because of the liability to become thrown offby the action set up in the passages through the atmospheric pressure,producing what is commonly termed siphoning, the water seal is renderedunreliable to a greater or less extent. To overcome this defect, it isthe common practice at the present time to connect the air-space in thetrap-body above the water seal directly with the atmosphere by avent-pipe carried from the trap to the outside of the building,where theend of the pipe is left open to the atmosphere.

The present invention has for its object, chiefly, to prevent a trap ofthis description having a water seal from siphoning or emptying thewater-seal chamber without employing a vent-pipe, thereby materiallyreducing the cost of the trap and the expense of setting up andconnecting it.

This improvement is of advantage also in situations where a trap alreadyset cannot be connected with the outer atmosphere by a vent-pipe exceptat considerable expense or by carrying the vent-pipe either on theinside or the outside of the building in exposed or unsightly positions.

To such end and object my said invention comprises certain novel partsand combination of parts. including a novel construction of trap-bodyhaving a circuitous chamber or bend provided with a straight member atone end connecting the trap with the waste-pipe from the basin-sink orother receptacle and at the opposite end a coupling connecting the bendwith a waste-pipe or a sewer-pipe, the said coupling having a centralpassage correwalls of the siphon passage or bend, standing v clear ofthe internal surfaces in the body of the coupling, so as to break orinterrupt the continuity of the interior surfaces of the siphon at theoutlet end.

The construction of trap to which I have applied the presentimprovement, as represented in the drawing, consists of a trap-bodyhaving-an inlet in the top, from which a tube f extends upward toconnect with the wastewater outlet in the sink or basin, and on one sideof this outlet the trap-body is enlarged to form a chamber a toacconimodatea swinging valve 7). This valve consists of aflat diskfitting closely to a seat around the inlet-aperture and hinged at oneside of the opening to swing laterally and uncover the inlet under theweight of the descending body of water. A counterweight a, connected tothe valve on the opposite side of its hinge, returns the valve and holdsit to its seat on the inlet after the downflowing water has passed intothe trap. In the side of the valve-chamber w an inletaperture k isconnected permanently with a source of clear water under pressure by apipe m, having a hand-operated shut-off valve 12, by means of which thewater is turned on or shut off. The pipe m being connected with eitherthe cold-water pipe or the hotwater pipe, furnishes a means al\ *ays athand for flushing the trap and for cleaning all the interior surfaces inan effective and thorough manner. In this clean-water pipe between thevalve 71 and the trap-body a check-valve p is sometimes placed as anadditional security to close communication between the building andparts of the trap-body below the valve Z). This check-valve is sometimescalled for as a precaution to prevent any possibility of foul gasesbeing forced by a back pressure in the sewer-pipe through the water sealof the trap and through the clean-water pipe, and so into the room, insituations where the water being shut off and the faucets accidentallyleft open and escape of gases from the trapbody below the valve 6 mightoccur. These conditions would be liable to happen when a building standsvacant for a considerable time and there is no flow of waste water intothe trap to maintain the water seal.

The body 8 of the trap is connected to the valve-chamber by a slip-jointand a screwthreaded clamping-ring t. A rubber packing w in a recess inthe ring is compressed and confined in place around the joint byscrewing down the ring.

The coupling on the outlet end of the waterseal chamber 8 is formed ofthe two members 2 5, the top member 2 being joined to the lower member5bya screw-threadedfiange 6, fitted to a threaded socket in the topof'the latter member and making a tight joint against a shoulder on theinside. The way or passage through the top member 2 is approximately thesame diameter internally as the end 4 of the siphon s where it joins thecoupling, so that the interior surfaces of the passage are practicallycontinuous with the internal surfaces of the siphon. The end 3 of thepassage through the upper member extends into the lower member for ashort distance below the joint 6 and is surrounded by a rim beveled to athin edge. The body 5 of the coupling is of larger diameter than this Ilower end of the member 2, which it incloses,

so that the walls'stand clear of the beveled rim 3, and below thisenlarged portion the coupling terminates in a, cylindrical end providedwith a gland or screw-threaded ring, by which the waste-pipe 7 issecured to the end of the coupling-body. A packing 10 being placed inthe gland produces a gas-tight joint. The effect of this break in thecontinuity of the internal surfaces in this part of the passage-way ofthe trap is to prevent the atmospheric pressure from setting up a flowin the water from the seal over the head in the trapbody, therebycausing the trap to siphon or draw off the water until the quantity inthe bend is reduced below the sealing-point. Breaking the film of waterin this manner between the water seal and the body of water in thewaste-pipe or sewer-pipe below the trap prevents such siphoning actionand insures at all times the retention of the water in the trap to thesealing-level.

Having thus fully described my invention, what I claim as new therein,and desire to secure by Letters Patent, is.

The combination with a trap-body having a depressed portion containing awater seal, of a coupling for uniting the outlet end-of the trap withthe waste-pipe, consisting of two members, one being connected directlyto the trap and having its outer end terminating in adownwardly-extending rim immediately adjacent to the overflow of thetrap, and the other part being of greater diameter than the saidterminal rim and surrounding the same so as to leave a clear spacebetween the rim and the inner wall of the said second part,substantially as set forth.

In testimony whereof I have signed my name in the presence of twosubscribing witnesses.

JOHN E. KEYT. Witnesses:

EDWARD E. OSBORN, M. REGNER.

